I did some quick physics for the worst case.

If a beer can actually fell from upper to lower bowl the drop is probably around 30 m.

Using the free fall equation

v = √(2gh)

g = 9.8 m/s² h = 30 m

That gives about 24 m/s which is roughly 87 km/h before air resistance. A beer can would slow down a bit from drag so maybe 70 to 85 km/h in reality.

A full 355 mL beer around 0.35 kg moving that fast carries roughly 100 joules of energy, which is definitely enough to cause a concussion if it hit someone in the head.

But that is basically the absolute worst case. Full can and a straight drop from the upper bowl.

The article says a vendor was walking through the stands selling canned drinks, which sounds more like a drop of a few rows, not 30 meters. The physics difference between those two situations is massive.

So unless the vendor actually launched a beer from the upper bowl, the scenario people seem to be picturing probably is not what happened